How Robbers Did Their Dirty Deeds Before Foursquare

There’s a very easy way to find out if someone is home or not: you phone their fixed phone number. If no one answers, chances are the house is empty. If you really want to make sure, you can simply check if the lights are on.

And yes, robbers actually used these tactics to rob people’s house for ages; this is why, ahead of summer vacations, you’ll see advice in magazines to have a friend periodically visit your house, turn the lights on and generally create the impression the house is not abandoned.